improvements

* chance to continue on mismatch url for redirectTab * support empty field selectors * add Extractor.results() * add ExtractResult.walk(), ExtractResult.visit() * add ! directive to click elements * code optimize
fix task running state
2021-04-20 14:20:05 +08:00 · 2021-04-20 12:01:10 +08:00 · 2021-04-20 12:00:59 +08:00 · 2021-04-19 15:58:04 +08:00 · 2020-06-16 14:45:36 +08:00 · 2020-01-17 11:01:13 +08:00
35 changed files with 6119 additions and 597 deletions
--- a/.gitignore
+++ b/.gitignore
@ -1,2 +1,154 @@
+# File created using '.gitignore Generator' for Visual Studio Code: https://bit.ly/vscode-gig
+
+# Created by https://www.gitignore.io/api/visualstudiocode,macos,node
+# Edit at https://www.gitignore.io/?templates=visualstudiocode,macos,node
+
+### macOS ###
+# General
 .DS_Store
-Thumbs.db
+.AppleDouble
+.LSOverride
+
+# Icon must end with two \r
+Icon
+
+# Thumbnails
+._*
+
+# Files that might appear in the root of a volume
+.DocumentRevisions-V100
+.fseventsd
+.Spotlight-V100
+.TemporaryItems
+.Trashes
+.VolumeIcon.icns
+.com.apple.timemachine.donotpresent
+
+# Directories potentially created on remote AFP share
+.AppleDB
+.AppleDesktop
+Network Trash Folder
+Temporary Items
+.apdisk
+
+### Node ###
+# Logs
+logs
+*.log
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+lerna-debug.log*
+
+# Diagnostic reports (https://nodejs.org/api/report.html)
+report.[0-9]*.[0-9]*.[0-9]*.[0-9]*.json
+
+# Runtime data
+pids
+*.pid
+*.seed
+*.pid.lock
+
+# Directory for instrumented libs generated by jscoverage/JSCover
+lib-cov
+
+# Coverage directory used by tools like istanbul
+coverage
+*.lcov
+
+# nyc test coverage
+.nyc_output
+
+# Grunt intermediate storage (https://gruntjs.com/creating-plugins#storing-task-files)
+.grunt
+
+# Bower dependency directory (https://bower.io/)
+bower_components
+
+# node-waf configuration
+.lock-wscript
+
+# Compiled binary addons (https://nodejs.org/api/addons.html)
+build/Release
+
+# Dependency directories
+node_modules/
+jspm_packages/
+
+# TypeScript v1 declaration files
+typings/
+
+# TypeScript cache
+*.tsbuildinfo
+
+# Optional npm cache directory
+.npm
+
+# Optional eslint cache
+.eslintcache
+
+# Optional REPL history
+.node_repl_history
+
+# Output of 'npm pack'
+*.tgz
+
+# Yarn Integrity file
+.yarn-integrity
+
+# dotenv environment variables file
+.env
+.env.test
+
+# parcel-bundler cache (https://parceljs.org/)
+.cache
+
+# next.js build output
+.next
+
+# nuxt.js build output
+.nuxt
+
+# rollup.js default build output
+dist/
+
+# Uncomment the public line if your project uses Gatsby
+# https://nextjs.org/blog/next-9-1#public-directory-support
+# https://create-react-app.dev/docs/using-the-public-folder/#docsNav
+# public
+
+# Storybook build outputs
+.out
+.storybook-out
+
+# vuepress build output
+.vuepress/dist
+
+# Serverless directories
+.serverless/
+
+# FuseBox cache
+.fusebox/
+
+# DynamoDB Local files
+.dynamodb/
+
+# Temporary folders
+tmp/
+temp/
+
+### VisualStudioCode ###
+.vscode/*
+!.vscode/settings.json
+!.vscode/tasks.json
+!.vscode/launch.json
+!.vscode/extensions.json
+
+### VisualStudioCode Patch ###
+# Ignore all local history of files
+.history
+
+# End of https://www.gitignore.io/api/visualstudiocode,macos,node
+
+# Custom rules (everything added below won't be overriden by 'Generate .gitignore File' if you use 'Update' option)
+
--- a/images/extnsion.png
+++ b/images/extnsion.png
--- a/package-lock.json
+++ b/package-lock.json
--- a/package.json
+++ b/package.json
@ -0,0 +1,17 @@
+{
+    "name": "data-extractor",
+    "scripts": {
+        "dev": "webpack --mode=development --devtool=inline-source-map --watch",
+        "prod": "webpack --mode=production"
+    },
+    "devDependencies": {
+        "@types/chrome": "0.0.91",
+        "@types/node": "^13.1.6",
+        "copy-webpack-plugin": "^5.1.1",
+        "ts-loader": "^6.2.1",
+        "tslint": "^5.20.1",
+        "typescript": "^3.7.4",
+        "webpack": "^4.41.5",
+        "webpack-cli": "^3.3.10"
+    }
+}
--- a/popup/tip.js
+++ b/popup/tip.js
@ -1,14 +0,0 @@
-$().ready(
-    () => {
-        $("#link-extension-detail").on('click', () => {
-            chrome.tabs.create({
-                'url': `chrome://extensions/?id=${chrome.runtime.id}`
-            });
-        })
-        $("#link-document").on('click', () => {
-            chrome.tabs.create({
-                'url': `https://git.jebbs.co/jebbs/data-extracter-extesion`
-            });
-        })
-    }
-);
--- a/readme.md
+++ b/readme.md
@ -5,130 +5,242 @@ DataExtracter helps you quickly extract data from any web pages.

 All you need to do is:

- Find out the selectors (JQuery selectors) for target data
+- Find out the selectors for target data
 - Type scripts in the console of `extension backgroud page`, as introduced bellow.

- ![](images/console.png)
+ ![](template/assets/console.png)

 ## Qucik Start

 Extract current page
+
 ```js
-new Extractor().task(".list-item", ["a.title", "p.content"]).start();
+$('.item', ['a', 'a@href']);
+new Extractor().task('.item', ['a', 'a@href']).start();
+// fieldSelectors can be empty strings if items have no child to select
+new Extractor().task('.item a', ['', '@href']).start();
 ```

+> `$(...args)` is the short form of `new Extractor().task(...args).start();`, which is introduced later.
+
 Extract multiple pages (1-10, interval 1)

 ```js
-new Extractor().task(".list-item", ["a.title", "p.content"],"http://sample.com/?pn=${page}", 1, 10, 1).start();
+$('.item', ['a', 'a@href'],"http://sample.com/?pn=${page}", 1, 10, 1);
 ```

 Extract multiple urls (list)

 ```js
-new Extractor().task(".list-item", ["a.title", "p.content"],["http://sample.com/abc","http://sample.com/xyz"]).start();
+$('.item', ['a', 'a@href'],["http://sample.com/abc","http://sample.com/xyz"]);
 ```

 Extract specified pages (1,3,5)

 ```js
-new Extractor().task(".list-item", ["a.title", "p.content"], "http://sample.com/?pn=${page}", [1, 3, 5]).start();
+$('.item', ['a', 'a@href'], "http://sample.com/?pn=${page}", [1, 3, 5]);
 ```

-## Extractor.task() Signitures
+## Task Call Signitures

 ```ts
-// a task extracting data from current page
-task(itemsSelector:string, fieldSelectors:string[])
-// a task extracting data from a range of pages
-task(itemsSelector:string, fieldSelectors:string[], urlTemplate:string, from:number, to:number, interval:number)
-// a task extracting data from a list of pages
-task(itemsSelector:string, fieldSelectors:string, urlTemplate:string, pages:number[])
-// a task extracting data from a list of pages
-task(itemsSelector:string, fieldSelectors:string[], urls:string[])
-// a task extracting data of urls which extracted from last task result
-task(itemsSelector:string, fieldSelectors:string[], urls:ExtractResult)
+// extract data from current page
+function (itemsSelector:string, fieldSelectors:string[])
+// extract data from a range of pages
+function (itemsSelector:string, fieldSelectors:string[], urlTemplate:string, from:number, to:number, interval:number)
+// extract data from a list of pages
+function (itemsSelector:string, fieldSelectors:string, urlTemplate:string, pages:number[])
+// extract data from a list of pages
+function (itemsSelector:string, fieldSelectors:string[], urls:string[])
+// extract data of urls which extracted from last task result
+function (itemsSelector:string, fieldSelectors:string[], urls:ExtractResult)
 ```

-## Advanced Usage
+## Stop Tasks

-### Stop Tasks
+Close the target tab, in which current tasks is running.

-Tasks wait for their target elements' appearance, given some elements were loaded asynchronously.
+Or use `job.stop()`:

-But if you typed wrong selectors, the task waits forever for  elements which don't exists.
+```js
+job = new Extractor().task('.search-list-item', ['a@href'], ["http://sample.com/abc"])
+    .task('list-item', ["a.title", "p.content"])
+    .start();
+job.stop();
+```

-The only way to stop tasks before its finish, is `Closing the host tab`.
+> Next time you call `job.start();`, the job will continues from where it stopped.

-### Extract Attributes.
+## Extract Attributes

 e.g.: link text and target (use 'selector@attribute')

 ```js
-new Extractor().task('.list-item', ['a.title', 'a.title@href']).start();
+new Extractor().task('.item', ['a', 'a@href']).start();
 ```

+## Click Selected Elements
+
+The following clicks selected links and extracts link `text` and `href`
+
+```js
+new Extractor().task('.item', ['!a', 'a@href']).start();
+```
+
+## Advanced Usage
+
 ### Use Task Chain.

 e.g.: Collect links from `http://sample.com/abc`, then, Extract data of each link

 ```js
-new Extractor()
-    .task('.search-list-item', ['.item a@href'], ["http://sample.com/abc"])
+e = new Extractor()
+e.task('.search-list-item', ['a@href'], ["http://sample.com/abc"])
    .task('list-item', ["a.title", "p.content"])
    .start();
 ```

-### Save Result of Any Task
+### Extractor Options

-To a multiple task (chain) Extractor `e`:
+Specify extra options, to make task do some actions before scrape the data.
+
+```js
+var job = new Extractor({ "scrollToBottom": 1 });
+```
+
+Available options:
+
+- `scrollToBottom`: Try scroll pages to the bottom, some elements are loaded only we user need them.
+
+
+### Export Result of Any Task
+
+To a multiple task Extractor `e`:

 ```js
 e = new Extractor()
-e.task('.search-list-item', ['.item a@href'], ["http://sample.com/abc"])
+e.task('.search-list-item', ['a@href'], ["http://sample.com/abc"])
    .task('list-item', ["a.title", "p.content"])
    .start();
 ```

-User will be asked to save  the final result when it finishes.
+User will be asked to export the final result when it finishes.

-Incase you want to save it again, use:
+Incase you want to export it again, use:

 ```js
-e.save()
+e.export()
 ```

-You may want to save another task's result, other than the final:
+To export another task result, other than the final one:

 ```js
-// save the result of first task
+// export the result of first task
 // to the example above, that is a list of urls
-e.save(1)
+e.export(0)
+// export the result of second task
+e.export(1)
 ```

+## Task Management
+
+### Continue Tasks
+
+Sometimes, it's hard to finish them in an single execution, that why we need "Continuing of Tasks".
+
+You can always continue tasks by start it again, not matter in what phase it stops.
+
+```js
+e.start()
+```
+
+The `Extractor` kept the execution state, and starts from where it stopped.
+
 ### Restart Tasks

-In cases some later task fails, you don't need to restart all task.
+What if I don't like to continue from last state, but restart certain tasks?

-Here we have 2 tasks:
+```js
+// restart all tasks
+e.restart(0)
+// restart from 2nd task
+e.restart(1)
+```
+
+### Save & Load State
+
+It may also be hard to finish tasks in even a single day, we need a way to save current state, and come back tommorow.
+
+Create and run an extractor:

 ```js
 e = new Extractor()
-e.task('.search-list-item', ['.item a@href'], ["http://sample.com/abc"])
+e.task('.search-list-item', ['a@href'], ["http://sample.com/abc"])
    .task('list-item', ["a.title", "p.content"])
    .start();
 ```

-Suppose the second task fails, we can restart and continue from the task 2:
+Save the state:

 ```js
-e.restart(2);
+e.save();
 ```

-If you'd like restart all task, use:
+Load the state:
+
+Open the popup window, upload the saved state file. Then, and in the backgroud console:

 ```js
+e = new Extractor().load();
 e.start();
-// or
-e.restart();
+```
+
+> The uploaded state will be cleaned in 30 seconds, if you don't load it.
+
+## Watch Mode
+
+Watch mode tries to exract data from every page you visit **in current window**.
+
+```js
+e = new Extractor();
+e.task('.search-list-item', ['a@href'], ["http://sample.com/abc"])
+    .task('list-item', ["a.title", "p.content"]);
+e.watch(1); // start watching for first task
+```
+
+To stop watching, you can either `close current window`, or:
+
+```js
+e.stop();
+```
+
+## Results Operation
+
+To get the results of a task:
+
+```js
+let results = job.results(0);
+```
+
+Visit URLs (if any) in the results one by one:
+
+```js
+results.visit();
+```
+
+Walk through all results one by one:
+
+```js
+results.walk((row,col,value)=>{console.log(value)});
+```
+
+## Developpment
+
+Clone this project and execute:
+
+```sh
+npm i
+npm run prod
+# or
+npm run dev
 ```
--- a/scripts/background.js
+++ b/scripts/background.js
@ -1,14 +0,0 @@
-chrome.runtime.onMessage.addListener(function (message, sender, sendResponse) {
-    if (message.from === "DataExtracter:Extract") {
-        if (!testArgs(...message.args)) {
-            sendResponse(signitures);
-            return;
-        }
-        extract(...message.args).catch(
-            err => {
-                console.log(err);
-                alert(err);
-            }
-        );
-    }
-});
--- a/scripts/content.js
+++ b/scripts/content.js
@ -1,58 +0,0 @@
-function extract(...args) {
-    let message = {
-        from: "DataExtracter:Extract",
-        args: args
-    }
-    chrome.runtime.sendMessage(message, r => {
-        if (r) console.log(r);
-    });
-}
-
-chrome.runtime.onMessage.addListener(
-    function (request, sender, sendResponse) {
-        if (!request.from) return;
-        let [ext, act] = request.from.split(":");
-        if (ext.toLowerCase() !== 'dataextracter') return;
-        // console.log(request);
-        switch (act.toLowerCase()) {
-            case "extract":
-                let data = extractTabData(request.itemsSelector, request.fieldSelectors);
-                if (sendResponse) sendResponse(data);
-                break;
-            case "gotourl":
-                window.location.replace(request.url);
-                if (sendResponse) sendResponse(request.url);
-                break;
-            case "reportin":
-                if (sendResponse) sendResponse(request.from);
-                break;
-            case "queryurl":
-                if (sendResponse) sendResponse(window.location.href);
-                break;
-            default:
-                break;
-        }
-    }
-);
-
-function extractTabData(itemsSelector, fieldSelectors) {
-    let fieldNotFound = false;
-    let results = $(itemsSelector).toArray().map(
-        item => {
-            return fieldSelectors.map(
-                selector => {
-                    let [cls, attr] = selector.split('@').slice(0, 2);
-                    // TODO: close tab to cancel task tip
-                    if (fieldNotFound) return;
-                    let fieldVals = $(item).find(cls).toArray();
-                    if (!fieldVals.length) {
-                        fieldNotFound = true;
-                        return;
-                    }
-                    return fieldVals.map(find => attr ? find[attr] : find.textContent.trim()).join('\n')
-                }
-            )
-        }
-    );
-    return fieldNotFound ? [] : results
-}
--- a/scripts/extract.js
+++ b/scripts/extract.js
@ -1,191 +0,0 @@
-/**
- * Extract data from current tab / multiple urls.
- * @param {string} itemsSelector items selectors for selecting items (data rows)
- * @param {Array<string>} fieldSelectors fields selectors for selecting fields (data columns) under each item
- * @param {...any} args url list / url templates, page numers, either [from, to, interval] or [...pages]
- */
-async function extract(itemsSelector, fieldSelectors, ...args) {
-    let result = await getData(itemsSelector, fieldSelectors, ...args);
-    if (confirm(
-            `Click confirm to download if the sample data looks good (${result.data.length} items)：\n\n${result.toString(50) || "- Empty -"}`
-        )) {
-        saveFile(result, "text/csv");
-    }
-}
-
-/**
- * Extract data from current tab / multiple urls.
- * @param {string} itemsSelector items selectors for selecting items (data rows)
- * @param {Array<string>} fieldSelectors fields selectors for selecting fields (data columns) under each item
- * @param {...any} args url list / url templates, page numers, either [from, to, interval] or [...pages]
- */
-async function getData(itemsSelector, fieldSelectors, ...args) {
-    if (!testArgs(itemsSelector, fieldSelectors, ...args))
-        throw new Error(`Invalid call arguments.\n\n${signitures}\n\n`);
-    let urls = [];
-    if (args.length) {
-        let arg = args.shift();
-        if (arg instanceof Array) {
-            urls = arg;
-        } else if (arg instanceof ExractResult) {
-            urls = arg.squash().filter(v => !!v);
-        } else {
-            let urlTempl = arg;
-            if (urlTempl) {
-                if (args[0] instanceof Array) {
-                    urls = args[0].map(p => urlTempl.replace("${page}", p));
-                } else if (args.length >= 3) {
-                    let from = args.shift();
-                    let to = args.shift();
-                    let interval = args.shift();
-                    for (let i = from; i <= to; i += interval) {
-                        urls.push(urlTempl.replace("${page}", i));
-                    }
-                }
-            }
-        }
-    }
-    let data = [];
-    let tab = await getActiveTab(true) || await getActiveTab(false);
-    if (!tab) throw new Error("Cannot find active tab.");
-    return new Promise((resolve, reject) => {
-        let pms;
-        if (urls.length) {
-            pms = urls.reduce((p, url) => p.then(
-                results => {
-                    data.push(...results);
-                    return redirectTab(tab, url).then(
-                        () => extractTabData(tab, itemsSelector, fieldSelectors)
-                    );
-                },
-                () => p
-            ), Promise.resolve([]));
-        } else {
-            pms = extractTabData(tab, itemsSelector, fieldSelectors);
-        }
-        pms.then(
-            results => {
-                data.push(...results);
-                resolve(new ExractResult(data));
-            },
-            err => reject(err)
-        );
-    });
-}
-
-function redirectTab(tab, url) {
-    let curUrl = "";
-    return queryUrl(tab)
-        .then(u => {
-            if (url !== u) {
-                curUrl = u;
-                let req = {
-                    from: "GotoUrl",
-                    url: url
-                }
-                sendMessage(tab, req);
-            }
-        })
-        .then(() => queryUrl(tab, curUrl))
-        .then(() => reportIn(tab));
-}
-
-/**
- * extract data in from the target tab.
- * @param {any} tab target tab
- * @param {string} itemsSelector items selectors for selecting items (data rows)
- * @param {Array<string>} fieldSelectors fields selectors for selecting fields (data columns) under each item
- * @returns {Promise<string[]>} a promise of extracted data
- */
-function extractTabData(tab, itemsSelector, fieldSelectors) {
-    let req = {
-        from: "Extract",
-        itemsSelector: itemsSelector,
-        fieldSelectors: fieldSelectors
-    }
-    let cond = r => r && r.length;
-    return sendMessage(tab, req, cond);
-}
-
-/**
- * get report in from the target tab, usually used to detect if the content script is ready.
- * @param {any} tab target tab
- * @returns {Promise<string>} a promise of the report in message
- */
-function reportIn(tab) {
-    let req = {
-        from: "ReportIn"
-    }
-    let cond = r => r == req.from;
-    return sendMessage(tab, req, cond);
-}
-
-/**
- * get the url of the target tab
- * @param {any} tab target tab
- * @param {string} urlExcluded if specified, queryUrl resolves only when response not equals to urlExcluded
- * @returns {Promise<string>} a promise of the url
- */
-function queryUrl(tab, urlExcluded) {
-    let req = {
-        from: "QueryUrl"
-    }
-    let cond = url => url && (!urlExcluded || (urlExcluded && urlExcluded != url));
-    return sendMessage(tab, req, cond);
-}
-
-/**
- * Repeatedly sending a message to target tab until the response is detected good.
- * @param {object} tab the table where to send the message
- * @param {object} req the request data.
- * @param {function} cond success condition function, r:any=>boolean
- * @param {number} interval interval for detecting
- * @return {Promise} a promise of the response.
- */
-function sendMessage(tab, req, cond, interval) {
-    req.from = "DataExtracter:" + req.from;
-    interval = interval || 500;
-    return new Promise((resolve, reject) => {
-
-        loop();
-
-        async function loop() {
-            console.log("request for", req.from);
-            let tabAvailable = await getTabByID(tab.id);
-            if (!tabAvailable) {
-                reject("Task interupted due to the target tab is closed.");
-                return;
-            }
-
-            chrome.tabs.sendMessage(tab.id, req, r => {
-                if (!cond || cond(r)) {
-                    resolve(r);
-                } else {
-                    setTimeout(() => {
-                        loop();
-                    }, interval);
-                }
-            });
-        }
-    });
-}
-
-async function getActiveTab(currentWindow) {
-    return new Promise((resolve, reject) => {
-        chrome.tabs.query({
-            active: true,
-            currentWindow: currentWindow
-        }, function (tabs) {
-            resolve(tabs[0]);
-        })
-    })
-}
-
-async function getTabByID(id) {
-    return new Promise((resolve, reject) => {
-        chrome.tabs.get(id, function (tab) {
-            chrome.runtime.lastError;
-            resolve(tab);
-        })
-    })
-}
--- a/scripts/extractor.js
+++ b/scripts/extractor.js
@ -1,111 +0,0 @@
-class Extractor {
-    constructor() {
-        this._tasks = [];
-        this._results = {};
-    }
-    /**
-     * Add a task to Extractor. \n
-     * One Extractor could has multiple tasks, which orgnized in a task chian.
-     * Later task will use previous task result as input (target url list).
-     * So only the first task can have target url arguments, while later tasks can't.
-     * @param {...any} args itemsSelector, fieldSelectors, and more args to specify target urls.
-     */
-    task(...args) {
-        if (!testArgs(...args))
-            throw new Error(`Invalid call arguments.\n\n${signitures}\n\n`);
-        // given >2 arguments means the task specifies target page, 
-        // so it won't accept last task result as url list.
-        // in this case, former tasks are useless, can be cleared.
-        if (args.length > 2) this.clear();
-        this._tasks.push(args);
-        return this;
-    }
-    /**
-     * Clear tasks and caches.
-     */
-    clear() {
-        this._tasks = [];
-        this._results = [];
-    }
-    /**
-     * Start the task chain.
-     */
-    async start() {
-        if (!this._tasks.length) {
-            console.log('No task to run.');
-            return;
-        }
-        return this._tasks.reduce((pms, args, i, tasks) => {
-            return pms.then(
-                result => {
-                    if (result === undefined) return getData(...args);
-                    this._results[tasks[i - 1]] = result;
-                    return getData(...args, result);
-                });
-        }, Promise.resolve(undefined)).then(
-            result => {
-                this._results[this._tasks[this._tasks.length - 1]] = result;
-                this.save();
-            }
-        ).catch(err => console.log(err));
-    }
-    /**
-     * restart from specified task, but don't restart the previous tasks.
-     * @param {number} taskid from which restart the tasks
-     */
-    async restart(taskid) {
-        taskid = this._checkTaskId(taskid, 1);
-        if (!taskid) return;
-        if (taskid == 1) {
-            this.start();
-            return;
-        }
-        let cache = this._results[this._tasks[taskid - 2]];
-        if (!cache) {
-            console.log(`No result cache for task (id ${taskid}). \nMake sure call ".start()" before ".restart()"?`);
-            return;
-        }
-        return this._tasks.slice(taskid - 1).reduce((pms, args, i, tasks) => {
-            return pms.then(
-                result => {
-                    this._results[tasks[i - 1]] = result;
-                    return getData(...args, result);
-                });
-        }, Promise.resolve(cache)).then(
-            result => {
-                this._results[this._tasks[this._tasks.length - 1]] = result;
-                this.save();
-            }
-        ).catch(err => console.log(err));
-    }
-    /**
-     * Save result of a task
-     * @param {number} taskid which task id to save.
-     */
-    save(taskid) {
-        taskid = this._checkTaskId(taskid, this._tasks.length);
-        if (!taskid) return;
-        const result = this._results[this._tasks[taskid - 1]];
-        if (!result) {
-            console.log(`No task result for id (${taskid}). Forget to call ".start()"?`);
-            return;
-        }
-        if (confirm(
-                `Click confirm to download if the sample data looks good (${result.data.length} items)：\n\n${result.toString(50) || "- Empty -"}`
-            )) {
-            saveFile(result, "text/csv");
-        }
-    }
-    _checkTaskId(id, defaultId) {
-        if (!this._tasks.length) {
-            console.log("No task found.");
-            return 0;
-        }
-        if (defaultId && id === undefined || this.task === null) id = defaultId;
-        if (isNaN(id) || id < 1 || id > this._tasks.length) {
-            console.log(`Invalid task id. Rang(1-${this._tasks.length})`);
-            return 0;
-        }
-        return id
-    }
-}
--- a/scripts/jquery.min.js
+++ b/scripts/jquery.min.js
--- a/scripts/result.js
+++ b/scripts/result.js
@ -1,34 +0,0 @@
-class ExtractResult {
-    constructor(data) {
-        this._data = data || [];
-
-    }
-    row(index) {
-        return this._data[index];
-    }
-    column(index) {
-        return [...new Array(this._data.length).keys()].map(
-            i => this._data[i][index]
-        );
-    }
-    squash() {
-        return this._data.reduce((p, c) => p.concat(c), []);
-    }
-    get data() {
-        return this._data;
-    }
-    toString(rowsCount) {
-        let data = rowsCount > 0 ? this._data.slice(0, rowsCount) : this._data;
-        return data.slice().reduce(
-            (csv, lineCells) => {
-                let line = lineCells.reduce(
-                    (lineText, cell, idx) => {
-                        cell = '"' + cell.trim().replace(/"/g, '""') + '"';
-                        return lineText + cell + (idx == lineCells.length - 1 ? "" : ",")
-                    }, "");
-                return csv + line + "\n";
-            },
-            ""
-        );
-    }
-}
--- a/scripts/tools.js
+++ b/scripts/tools.js
@ -1,98 +0,0 @@
-const signitures = `
-# DataExtracter Help
----------------------------
-
-## Usage
-new Extractor().task(...args).task(...args).start();
-
-## Extractor.task() Signitures:
----------------------------
-
-task(itemsSelector:string, fieldSelectors:string[])
-task(itemsSelector:string, fieldSelectors:string[], url:string, from:number, to:number, interval:number)
-task(itemsSelector:string, fieldSelectors:string, url:string, pages:number[])
-task(itemsSelector:string, fieldSelectors:string[], urls:string[])
-task(itemsSelector:string, fieldSelectors:string[], urls:ExtractResult)
-
-See detail help in:
-https://git.jebbs.co/jebbs/data-extracter-extesion
-`.trim();
-
-
-function saveFile(data, mimeType, fileName) {
-    fileName = fileName || document.title || "result";
-    var blob;
-    if (typeof window.Blob == "function") {
-        blob = new Blob([data], {
-            type: mimeType
-        })
-    } else {
-        var BlobBuiler = window.BlobBuilder || window.MozBlobBuilder || window.WebKitBlobBuilder || window.MSBlobBuilder;
-        var builer = new BlobBuiler();
-        builer.append(data);
-        blob = builer.getBlob(mimeType)
-    }
-    var URL = window.URL || window.webkitURL;
-    var url = URL.createObjectURL(blob);
-    var link = document.createElement("a");
-    if ('download' in link) {
-        link.style.visibility = "hidden";
-        link.href = url;
-        link.download = fileName;
-        document.body.appendChild(link);
-        var j = document.createEvent("MouseEvents");
-        j.initEvent("click", true, true);
-        link.dispatchEvent(j);
-        document.body.removeChild(link)
-    } else if (navigator.msSaveBlob) {
-        navigator.msSaveBlob(blob, fileName)
-    } else {
-        location.href = url
-    }
-}
-
-function testArgs(...args) {
-    switch (args.length) {
-        case 0, 1:
-            return false;
-        case 2:
-            return args[0] && args[1] &&
-                (typeof args[0] == "string") &&
-                (args[1] instanceof Array) &&
-                testArrayVals(args[1], v => typeof v == "string");
-        case 3:
-            return args[0] && args[1] &&
-                typeof args[0] == "string" &&
-                args[1] instanceof Array &&
-                testArrayVals(args[1], v => typeof v == "string") &&
-                (
-                    (
-                        args[2] instanceof Array &&
-                        testArrayVals(args[2], v => typeof v == "string")
-                    ) || (
-                        args[2] instanceof ExtractResult
-                    )
-                );
-        case 4:
-            return args[0] && args[1] &&
-                typeof args[0] == "string" &&
-                args[1] instanceof Array &&
-                testArrayVals(args[1], v => typeof v == "string") &&
-                typeof args[2] == "string" &&
-                args[3] instanceof Array &&
-                testArrayVals(args[3], v => typeof v == "number");
-        case 6:
-            return args[0] && args[1] &&
-                typeof args[0] == "string" &&
-                args[1] instanceof Array &&
-                testArrayVals(args[1], v => typeof v == "string") &&
-                typeof args[2] == "string" &&
-                !isNaN(args[3]) && !isNaN(args[4]) && !isNaN(args[5]);
-        default:
-            return false;
-    }
-
-    function testArrayVals(arr, tester) {
-        return arr.reduce((p, c) => p && tester(c), true);
-    }
-}
--- a/src/background/actions.ts
+++ b/src/background/actions.ts
@ -0,0 +1,202 @@
+import { Actions, Request } from "../common";
+import { sendMessage, ResponseChecker } from "./messaging";
+import { logger } from "../common/logger";
+
+/**
+ * redirect tab to url.
+ * @param {any} tab target tab
+ * @param {string} url target URL
+ * @returns {Promise<string[]>} a promise of target URL
+ */
+export function redirectTab(tab: chrome.tabs.Tab, url: string, check?: boolean) {
+    return queryUrl(tab).then(u => {
+        if (url !== u) {
+            let req: Request = {
+                action: Actions.GOTO_URL,
+                url: url
+            }
+            let checker: ResponseChecker<string> = !check ? undefined : async (r, err, tryCount): Promise<string> => {
+                let queryErr: any;
+                let newURL = await queryUrl(tab).catch(e => queryErr = e);
+                if (queryErr) {
+                    throw queryErr;
+                }
+                if (newURL == url) return url;
+                if (
+                    confirm(`Cannot navigate to target url. 
+expected: ${url}\n
+actual:   ${newURL}\n
+Press OK to continue, Cancel to retry. Close the tab to stop`)
+                ) {
+                    return newURL;
+                }
+                return undefined;
+            }
+            return sendMessage<string>(tab, req, `Goto url: ${url}`, checker);
+        }
+    });
+}
+
+/**
+ * extract data in from the target tab.
+ * @param {any} tab target tab
+ * @param {string} itemsSelector items selectors for selecting items (data rows)
+ * @param {Array<string>} fieldSelectors fields selectors for selecting fields (data columns) under each item
+ * @returns {Promise<string[]>} a promise of extracted data
+ */
+export function extractTabData(tab: chrome.tabs.Tab, itemsSelector: string, fieldSelectors: string[], expectedURL?: string, askOnfail?: boolean) {
+    let req: Request = {
+        action: Actions.EXTRACT,
+        itemsSelector: itemsSelector,
+        fieldSelectors: fieldSelectors,
+        url: expectedURL,
+    }
+    let checker: ResponseChecker<string[][]> = (response, err, tryCount) => {
+        if (response.error) throw response.error;
+        let result = response.result;
+        if (!result || !result.length) {
+            if (
+                tryCount % 20 == 0 && (
+                    !askOnfail ||
+                    confirm('No data found in current page. \n\nContinue to next page?')
+                )
+            ) {
+                logger.warn(`Failed after ${tryCount} tries: ${tab.url}`)
+                return [];
+            } else {
+                return undefined;
+            }
+        }
+        return result;
+    };
+    return sendMessage<string[][]>(tab, req, 'Extract data from the tab...', checker);
+}
+
+/**
+ * ping target tab, usually used to detect if the content script is ready.
+ * @param {any} tab target tab
+ * @returns {Promise<boolean>} a promise of boolean value indicates if ping success
+ */
+export async function ping(tab, count = 1) {
+    let req = {
+        action: Actions.PING
+    }
+    let checker: ResponseChecker<string> = (r, e, c) =>
+        r.result == "pong" ? r.result : undefined;
+
+    let pong = await sendMessage<string>(tab, req, 'Check tab availability...', checker, 1000, 1000, count).catch(() => { });
+    return pong == "pong";
+}
+
+/**
+ * get the url of the target tab
+ * @param {any} tab target tab
+ * @returns {Promise<string>} a promise of the url
+ */
+export function queryUrl(tab: chrome.tabs.Tab) {
+    let req = {
+        action: Actions.QUERY_URL
+    }
+    return sendMessage<string>(tab, req);
+}
+
+/**
+ * get the url of the target tab
+ * @param {any} tab target tab
+ * @param {string} expected if specified, queryUrl resolves only when tab url equals to expected
+ * @returns {Promise<string>} a promise of the url
+ */
+export function scrollToBottom(tab: chrome.tabs.Tab) {
+    let req = {
+        action: Actions.SCROLL_BOTTOM
+    }
+    return sendMessage(tab, req, 'Scroll to page bottom...');
+}
+
+export async function createTab(url: string, active: boolean): Promise<chrome.tabs.Tab> {
+    return new Promise((resolve, reject) => {
+        findIncognitoWindow().then(
+            incognitoWindow => {
+                chrome.tabs.create({
+                    'url': url,
+                    'active': active,
+                    // createTab to incognito window first
+                    'windowId': incognitoWindow ? incognitoWindow.id : undefined
+                }, function (tab) {
+                    resolve(tab);
+                })
+            }
+        );
+    });
+}
+
+export async function findIncognitoWindow(): Promise<chrome.windows.Window> {
+    return new Promise((resolve, reject) => {
+        chrome.windows.getAll(
+            {
+                windowTypes: ['normal'],
+            },
+            (windows: chrome.windows.Window[]) => {
+                for (let window of windows) {
+                    if (window.incognito) {
+                        resolve(window);
+                        return;
+                    }
+                }
+                resolve(undefined);
+            }
+        );
+    });
+}
+
+export async function getCurrentWindow(): Promise<chrome.windows.Window> {
+    return new Promise((resolve, reject) => {
+        chrome.windows.getCurrent(
+            (windows: chrome.windows.Window) => {
+                return resolve(windows);
+            }
+        );
+    });
+}
+
+export async function getWindowByID(id: number) {
+    return new Promise<chrome.windows.Window>((resolve, reject) => {
+        chrome.windows.get(id, function (window) {
+            chrome.runtime.lastError;
+            resolve(window);
+        })
+    })
+}
+
+export async function CreateIncognitoWindow() {
+    return new Promise((resolve, reject) => {
+        chrome.windows.create(
+            <chrome.windows.CreateData>{
+                incognito: true,
+            },
+            (window: chrome.windows.Window) => {
+                resolve(window);
+            }
+        );
+    });
+}
+
+export async function getActiveTab(currentWindow: boolean): Promise<chrome.tabs.Tab> {
+    return new Promise((resolve, reject) => {
+        chrome.tabs.query({
+            active: true,
+            currentWindow: currentWindow
+        }, function (tabs) {
+            resolve(tabs[0]);
+        })
+    })
+}
+
+export async function getTabByID(id: number): Promise<chrome.tabs.Tab> {
+    return new Promise((resolve, reject) => {
+        chrome.tabs.get(id, function (tab) {
+            chrome.runtime.lastError;
+            resolve(tab);
+        })
+    })
+}
--- a/src/background/caches.ts
+++ b/src/background/caches.ts
@ -0,0 +1,31 @@
+import { logger } from "../common/logger";
+import { Actions } from "../common";
+import { messageSubscribers } from "./messaging";
+
+export class Caches {
+    private _state: string = "";
+    constructor() {
+        messageSubscribers.addListener(Actions.UPLOAD_STATE, (request, sender, sendResponse) => {
+            sendResponse('recieved!');
+            this.setState(request.fileName, request.state)
+        });
+    }
+    get state(): string {
+        let s = this._state;
+        this._state = "";
+        return s;
+    }
+    setState(name: string, content: string) {
+        this._state = content;
+        logger.info(`State (${name}) recieved. To load it: some_var = new Extractor().load()`);
+        // clear cache in 30 seconds
+        setTimeout(() => {
+            if (this._state) {
+                logger.info(`Uploaded state is cleaned after 30 second.`);
+                this._state = "";
+            }
+        }, 30000);
+    }
+}
+
+export const caches = new Caches();
--- a/src/background/extractor.ts
+++ b/src/background/extractor.ts
@ -0,0 +1,184 @@
+import { Task } from "./task";
+import { parseUrls, saveFile } from "./tools";
+import { createTab, getActiveTab, ping, redirectTab } from "./actions";
+import { logger } from "../common/logger";
+import { caches } from "./caches";
+import { ExtractResult } from "./result";
+
+export class Extractor {
+    private _tasks: Task[] = [];
+    private _running = false;
+    private _options: any = {};
+    constructor(options?) {
+        if (options) this._options = options;
+    }
+    static async ping(count: number = 1) {
+        let tab = await getActiveTab(true) || await getActiveTab(false);
+        let succ = await ping(tab, count);
+        if (!succ) {
+            logger.error('Cannot contact with active tab.');
+            return;
+        }
+    }
+    /**
+     * Save current state, in case we restore it later.
+     */
+    save() {
+        saveFile(JSON.stringify(this), 'application/json', 'state.json');
+    }
+    /**
+     * Restore previous state by loading from saved state.
+     */
+    load() {
+        let content = caches.state;
+        if (!content) {
+            logger.info('No state found. Please upload a saved state from the popup window first.');
+            return;
+        }
+        let state = JSON.parse(content);
+        this._options = state._options;
+        this._tasks = state._tasks.map(t => new Task(this._options, 'whaterver', ['whaterver']).load(t));
+        return this;
+    }
+    /**
+     * Add a task to Extractor. \n
+     * One Extractor could has multiple tasks, which orgnized in a task chian.
+     * If url arguments not given within later tasks, they will use previous task result as input (target url list).
+     * @param {...any} args itemsSelector, fieldSelectors, and more args to specify target urls.
+     */
+    task(...args: any) {
+        this._tasks.push(new Task(this._options, ...args));
+        return this;
+    }
+    /**
+     * Add a task to Extractor. \n
+     * One Extractor could has multiple tasks, which orgnized in a task chian.
+     * If url arguments not given within later tasks, they will use previous task result as input (target url list).
+     * @param {...any} args itemsSelector, fieldSelectors, and more args to specify target urls.
+     */
+    results(id?: number): ExtractResult {
+        id = this._checkTaskId(id);
+        if (id < 0) return;
+        return this._tasks[id].results;
+    }
+    /**
+     * Clear tasks and task caches.
+     */
+    clear() {
+        this._tasks = [];
+        return this;
+    }
+    /**
+     * Start the task chain.
+     */
+    start() {
+        return this._startTasks(0);
+    }
+    stop(id?: number) {
+        if (id !== undefined) {
+            id = this._checkTaskId(id);
+            if (id < 0) return;
+            this._tasks[id].stop();
+            return;
+        }
+        for (let i = 0; i < this._tasks.length; i++) {
+            this._tasks[i].stop();
+        }
+    }
+    watch(id: number) {
+        id = this._checkTaskId(id);
+        if (id < 0) return;
+        this._tasks[id].watch();
+    }
+    /**
+     * restart from specified task, but don't restart the previous tasks.
+     * @param {number} from where to restart the tasks, begins with 0
+     */
+    restart(from: number = 0) {
+        let id = this._checkTaskId(from, 0);
+        if (id < 0) return;
+        for (let i = id; i < this._tasks.length; i++) {
+            this._tasks[i].clean();
+        }
+        return this._startTasks(0);
+    }
+    async _startTasks(from: number) {
+        if (this._running) {
+            logger.info('The Extractor is running. Please wait..');
+            return;
+        }
+        if (!this._tasks.length) {
+            logger.info('No task to run.');
+            return;
+        }
+
+        let tab;
+        let task = this._tasks[0];
+        if (task.urls.length) {
+            // task specifies target urls, create new tab with first url for it
+            tab = await createTab(task.urls[0], false);
+        } else {
+            tab = await getActiveTab(true) || await getActiveTab(false);
+            let succ = await ping(tab);
+            if (!succ) {
+                logger.error('Cannot contact with active tab.');
+                return;
+            }
+        }
+        this._running = true;
+        return this._tasks.reduce((pms, task: Task, i: number) => {
+            return pms.then(
+                () => {
+                    if (i < from) return;
+                    if (i > 0) {
+                        let prevTask = this._tasks[i - 1];
+                        return task.execute(tab, prevTask.results);
+                    }
+                    return task.execute(tab);
+                });
+        }, Promise.resolve<void>(undefined)).then(
+            () => {
+                this._running = false;
+                this.export();
+            }
+        ).catch(err => {
+            this._running = false;
+            logger.error(err);
+        });
+    }
+    /**
+     * export result of a task to CSV
+     * @param {number} taskid which task id to save, begins with 0
+     */
+    export(taskid?: number) {
+        let id = this._checkTaskId(taskid, this._tasks.length - 1);
+        if (id < 0) return;
+        let results = this._tasks[id].results
+        let count = results.data.length
+        if (!count) {
+            logger.info(`No result for task #${id}. Forget to call ".start()"?`);
+            return;
+        }
+        results.header = this._tasks[id].fieldSelectors;
+        let msg = `
+Please confirm to download (${count} items)：
+
+${results.toString(50) || "- Empty -"}
+`.trim();
+        if (confirm(msg)) {
+            saveFile(results.toString(), "text/csv");
+        }
+    }
+    private _checkTaskId(id: number, defaultId?: number) {
+        if (!this._tasks.length) {
+            logger.info("No task found.");
+            return -1;
+        }
+        if (!isNaN(defaultId) && id === undefined) id = defaultId;
+        if (isNaN(id) || id < 0 || id >= this._tasks.length) {
+            logger.info(`Invalid task id. Rang(0-${this._tasks.length - 1})`);
+            return -1;
+        }
+        return id
+    }
+}
--- a/src/background/index.ts
+++ b/src/background/index.ts
@ -0,0 +1,14 @@
+import { Extractor } from "./extractor";
+
+declare global {
+    interface Window {
+        $: (...args: any) => void;
+        Extractor: any;
+    }
+}
+
+window.$ = function (...args) {
+    return new Extractor().task(...args).start();
+}
+
+window.Extractor = Extractor;
--- a/src/background/messaging.ts
+++ b/src/background/messaging.ts
@ -0,0 +1,150 @@
+import { Request, Actions, Response } from "../common";
+import { getTabByID } from "./actions";
+import { logger } from "../common/logger";
+
+
+export type ResponseCheckerSync<T> = (r: Response<T>, err: chrome.runtime.LastError, count: number) => T;
+export type ResponseCheckerAsync<T> = (r: Response<T>, err: chrome.runtime.LastError, count: number) => Promise<T>;
+export type ResponseChecker<T> = ResponseCheckerSync<T> | ResponseCheckerAsync<T>;
+/**
+ *  Sending a message to target tab repeatedly until the response is not undefined.
+ * @param {object} tab the table where to send the message
+ * @param {object} req the request data.
+ * @param {function} dataChecker (reulst:any, err:error, tryCount:number) => any. 
+ * Check and decide what value finally returns. 
+ * Return undefined to make 'sendMessage' retry. 
+ * Return MSG_USER_ABORT to cancel this promise.
+ * @param {number} interval retry interval, default: 500ms.
+ * @param {number} limit retry limit, default: 0, no limit.
+ * @param {string} log messages logged to console.
+ * @return {Promise} a promise of the response.
+ */
+export function sendMessage<T>(
+    tab: chrome.tabs.Tab,
+    req: Request,
+    log?: string,
+    dataChecker?: ResponseChecker<T>,
+    timeout?: number,
+    interval?: number,
+    limit?: number
+) {
+    timeout = timeout || 10;
+    interval = interval || 500;
+    limit = isNaN(limit) ? 0 : limit;
+    let count = 0;
+    return new Promise<T>((resolve, reject) => {
+
+        loop();
+
+        async function loop() {
+            logger.debug("Request for", Actions[req.action]);
+            let tabAvailable = await getTabByID(tab.id);
+            if (!tabAvailable) {
+                reject("Task interrupted due to the target tab is closed.");
+                return;
+            }
+
+            if (limit && count >= limit) {
+                reject(`sendMessage loop limit ${limit} reached.`);
+                return;
+            }
+            count++;
+            let timeout = setTimeout(() => { reject(`${Actions[req.action]} requset timeout after ${timeout}s`) }, 10000);
+            chrome.tabs.sendMessage(tab.id, req, async (r: Response<T>) => {
+                clearTimeout(timeout);
+                // check error but do nothing until dataChecker.
+                let err = chrome.runtime.lastError;
+                let [result, error] = await checkResponse(dataChecker, r, err, count);
+                if (error) {
+                    reject(error);
+                    return;
+                }
+                let flag = result !== undefined;
+                if (log) logger.info(log, flag ? '(OK)' : '(failed)');
+                if (flag) {
+                    resolve(result);
+                } else {
+                    setTimeout(() => {
+                        logger.debug('Invalid response', r, 'retry...');
+                        loop();
+                    }, interval);
+                }
+            });
+        }
+    });
+}
+
+async function checkResponse<T>(
+    dataChecker: ResponseChecker<T>,
+    response: Response<T>,
+    error: chrome.runtime.LastError,
+    tryCount: number
+): Promise<[T, string]> {
+    // response could be undefined if the content script is interrupted.
+    // don't check, tell sendMessage to retry.
+    if (!response) return [undefined, undefined];
+    if (!dataChecker) {
+        return [response.result, response.error];
+    }
+    let result: T;
+    let pms: T | Promise<T>;
+    try {
+        pms = dataChecker(response, error, tryCount);
+    } catch (err) {
+        return [undefined, err];
+    }
+    // don't catch if it's not a Promise
+    if (pms instanceof Promise) {
+        let checkerError: any;
+        pms = pms.catch(e => checkerError = e);
+        result = await pms;
+        if (checkerError) {
+            return [undefined, checkerError];
+        }
+    } else {
+        result = pms;
+    }
+    return [result, undefined];
+}
+
+export type ActionSubscriberSync = (request: Request, sender: chrome.runtime.MessageSender, sendResponse: (response?: any) => void) => void;
+export type ActionSubscriberAsync = (request: Request, sender: chrome.runtime.MessageSender, sendResponse: (response?: any) => void) => Promise<void>;
+export type ActionSubscriber = ActionSubscriberSync | ActionSubscriberAsync;
+
+class MessageSubscribers {
+    private listeners: { [key: number]: ActionSubscriber[] } = {};
+    addListener(action: Actions, subscriber: ActionSubscriber) {
+        this.listeners[action] || (this.listeners[action] = []);
+        this.listeners[action].push(subscriber);
+    }
+    removeListener(action: Actions, subscriber: ActionSubscriber) {
+        this.listeners[action] || (this.listeners[action] = []);
+        for (let i = 0; i < this.listeners[action].length; i++) {
+            if (this.listeners[action][i] == subscriber) {
+                this.listeners[action].splice(i, 1);
+                i--;
+            }
+        }
+        logger.debug(`${this.listeners[action].length} subscriber(s) remained for action ${Actions[action]}`);
+    }
+    getListeners(action: Actions): ActionSubscriber[] {
+        return this.listeners[action]
+    }
+}
+export const messageSubscribers = new MessageSubscribers();
+
+chrome.runtime.onMessage.addListener(function (request: Request, sender, sendResponse) {
+    let subscribers = messageSubscribers.getListeners(request.action);
+    if (!subscribers || !subscribers.length) {
+        sendResponse("Request not supported.");
+        return;
+    }
+    let promises: Promise<any>[] = [];
+    for (let subscriber of subscribers) {
+        let p = subscriber(request, sender, sendResponse);
+        if (p instanceof Promise) promises.push(p);
+    }
+    if (promises.length)
+        return Promise.all(promises);
+    return;
+});
--- a/src/background/result.ts
+++ b/src/background/result.ts
@ -0,0 +1,85 @@
+import { logger } from "../common/logger";
+import { getActiveTab, ping, redirectTab } from "./actions";
+import { parseUrls } from "./tools";
+
+export class ExtractResult {
+    private _header: string[];
+    private _data: string[][] = [];
+    constructor(data: string[][]) {
+        this._data = data || [];
+    }
+    row(index: number): string[] {
+        return this._data[index];
+    }
+    column(index: number): string[] {
+        return [...new Array(this._data.length).keys()].map(
+            i => this._data[i][index]
+        );
+    }
+    squash(): string[] {
+        return this._data.reduce((p, c) => p.concat(c), []);
+    }
+    set header(h: string[]) {
+        this._header = h
+    }
+    get data(): string[][] {
+        return this._data;
+    }
+    toString(rowsCount: number = 0): string {
+        let data = rowsCount > 0 ? this._data.slice(0, rowsCount) : this._data;
+        if (this._header && this._header.length) {
+            data.unshift(this._header);
+        }
+        return data.slice().reduce(
+            (csv, lineCells) => {
+                if (!lineCells || !lineCells.length) {
+                    return csv + "\n";
+                }
+                let line = lineCells.reduce(
+                    (lineText, cell, idx) => {
+                        cell = cell || "";
+                        cell = '"' + cell.trim().replace(/"/g, '""') + '"';
+                        return lineText + cell + (idx == lineCells.length - 1 ? "" : ",")
+                    }, "");
+                return csv + line + "\n";
+            },
+            ""
+        );
+    }
+    async walk(fn: (row: number, col: number, value: string) => void) {
+        let pms = Promise.resolve(null);
+        for (let i = 0; i < this._data.length; i++) {
+            let cells = this._data[i];
+            for (let j = 0; j < cells.length; j++) {
+                let row = i;
+                let col = j;
+                let value = cells[j];
+                pms = pms.then(
+                    () => fn(row, col, value)
+                )
+            }
+        }
+        return pms.catch(err => {
+            logger.error(err);
+        });
+    }
+    async visit() {
+        let urls = parseUrls(this);
+        let tab = await getActiveTab(true) || await getActiveTab(false);
+        let succ = await ping(tab);
+        if (!succ) {
+            logger.error('Cannot contact with active tab.');
+            return;
+        }
+        return urls.reduce(
+            (pms, url: string, i: number) => {
+                return pms.then(
+                    async () => {
+                        return redirectTab(tab, url, false);
+                    });
+            }, Promise.resolve<void>(undefined)
+        ).catch(err => {
+            logger.error(err);
+        });
+    }
+}
--- a/src/background/signiture.ts
+++ b/src/background/signiture.ts
@ -0,0 +1,71 @@
+import { ExtractResult } from "./result";
+
+export const signitures = `
+## Usage
+// single task
+$(...args);
+// managed task chains
+e = new Extractor();
+e.task(...args).task(...args).start();
+
+## Task Call Signitures:
+function(itemsSelector:string, fieldSelectors:string[]);
+function(itemsSelector:string, fieldSelectors:string[], url:string, from:number, to:number, interval:number);
+function(itemsSelector:string, fieldSelectors:string[], url:string, pages:number[]);
+function(itemsSelector:string, fieldSelectors:string[], urls:string[]);
+
+## Example:
+// extract all links text & url under '.item' elements
+// use 'selector@attr' to get attribute of the field elements
+$(".item", ["a", "a@href"]);
+
+## See Detailed Help:
+https://git.qjebbs.com/jebbs/data-extracter-extesion
+`.trim();
+
+export function testArgs(...args: any) {
+    switch (args.length) {
+        case 0:
+        case 1:
+            return false;
+        case 2:
+            return args[0] && args[1] &&
+                (typeof args[0] == "string") &&
+                (args[1] instanceof Array) &&
+                testArrayVals(args[1], v => typeof v == "string");
+        case 3:
+            return args[0] && args[1] &&
+                typeof args[0] == "string" &&
+                args[1] instanceof Array &&
+                testArrayVals(args[1], v => typeof v == "string") &&
+                (
+                    (
+                        args[2] instanceof Array &&
+                        testArrayVals(args[2], v => typeof v == "string")
+                    ) || (
+                        args[2] instanceof ExtractResult
+                    )
+                );
+        case 4:
+            return args[0] && args[1] &&
+                typeof args[0] == "string" &&
+                args[1] instanceof Array &&
+                testArrayVals(args[1], v => typeof v == "string") &&
+                typeof args[2] == "string" &&
+                args[3] instanceof Array &&
+                testArrayVals(args[3], v => typeof v == "number");
+        case 6:
+            return args[0] && args[1] &&
+                typeof args[0] == "string" &&
+                args[1] instanceof Array &&
+                testArrayVals(args[1], v => typeof v == "string") &&
+                typeof args[2] == "string" &&
+                !isNaN(args[3]) && !isNaN(args[4]) && !isNaN(args[5]);
+        default:
+            return false;
+    }
+
+    function testArrayVals(arr, tester) {
+        return arr.reduce((p, c) => p && tester(c), true);
+    }
+}
--- a/src/background/task.ts
+++ b/src/background/task.ts
@ -0,0 +1,178 @@
+import { parseUrls } from "./tools";
+import { queryUrl, redirectTab, scrollToBottom, extractTabData, findIncognitoWindow, getCurrentWindow, getWindowByID } from "./actions";
+import { testArgs, signitures } from "./signiture";
+import { ExtractResult } from "./result";
+import { messageSubscribers, ActionSubscriber } from "./messaging";
+import { Actions } from "../common";
+import { logger } from "../common/logger";
+
+export class Task {
+    private _data: { [key: string]: string[][] } = {};
+    private _data_keys: string[] = [];
+    private _options: any;
+    private _itemsSelector: string;
+    private _fieldSelectors: string[];
+    private _urls: string[] = [];
+    private _running = false;
+    private _listeners: ActionSubscriber[] = [];
+
+    constructor(options: any, ...arg: any);
+    constructor(options: any, itemsSelector: string, fieldSelectors: string[]);
+    constructor(options: any, itemsSelector: string, fieldSelectors: string[], url: string, from: number, to: number, interval: number);
+    constructor(options: any, itemsSelector: string, fieldSelectors: string[], url: string, pages: number[]);
+    constructor(options: any, itemsSelector: string, fieldSelectors: string[], urls: string[]);
+    constructor(options, ...args) {
+        if (!testArgs(...args))
+            throw new Error(`Invalid call arguments.\n\n${signitures}\n\n`);
+        this._options = options;
+        this._itemsSelector = args.shift();
+        this._fieldSelectors = args.shift();
+        this._urls = parseUrls(...args);
+    }
+    load(state: any): Task {
+        this._itemsSelector = state._itemsSelector;
+        this._data = state._data;
+        this._data_keys = state._data_keys;
+        this._itemsSelector = state._itemsSelector;
+        this._fieldSelectors = state._fieldSelectors;
+        this._urls = state._urls;
+        return this;
+    }
+    get urls(): string[] {
+        return this._urls;
+    }
+    get results(): ExtractResult {
+        let rs: string[][] = this._data_keys.reduce((p, c) => {
+            return p.concat(this._data[c]);
+        }, []);
+        return new ExtractResult(rs);
+    }
+    get fieldSelectors(): string[] {
+        return this._fieldSelectors;
+    }
+    clean(): Task {
+        this.stop();
+        this._data = {};
+        this._data_keys = [];
+        return this;
+    }
+    stop() {
+        this._running = false;
+        let listener: ActionSubscriber;
+        while (listener = this._listeners.pop()) {
+            messageSubscribers.removeListener(Actions.REPORT_NEW_PAGE, listener);
+        }
+    }
+    async watch() {
+        if (this._running) {
+            logger.info("The task is running. Please wait...");
+            return;
+        }
+        this._running = true;
+        let window = await findIncognitoWindow() || await getCurrentWindow();
+        if (!window) {
+            logger.info("No window to watch...");
+            return;
+        }
+        let watchTaskID = 0;
+        let listener: ActionSubscriber = async (request, sender, sendResponse) => {
+            let findWindow = await getWindowByID(window.id);
+            if (!findWindow) {
+                // stop watch on window close.
+                messageSubscribers.removeListener(Actions.REPORT_NEW_PAGE, listener);
+                return;
+            }
+            // only watch current window.
+            if (sender.tab.windowId != window.id) return;
+            let taskID = watchTaskID++;
+            logger.info(`Watcher #${taskID} starts.`);
+            let pm = this.makeOptionalTasks(sender.tab);
+            return pm.then(
+                () => extractTabData(sender.tab, this._itemsSelector, this._fieldSelectors, sender.tab.url, true)
+            ).then(
+                results => {
+                    if (results && results.length) {
+                        this.saveResult(results, sender.tab.url);
+                    }
+                    logger.info(`Watcher #${taskID} ends.`);
+                }
+            ).catch(
+                e => logger.error(`Watcher #${taskID} ends with:`, e)
+            )
+        }
+        this._listeners.push(listener);
+        messageSubscribers.addListener(Actions.REPORT_NEW_PAGE, listener);
+    }
+    async execute(tab: chrome.tabs.Tab, upstreamData?: ExtractResult): Promise<void> {
+        if (!tab) throw "No tab to execute the task.";
+        if (this._running) throw "The task is running. Please wait...";
+        this._running = true;
+        let urls = this._urls
+        if (!urls.length) {
+            if (upstreamData) {
+                urls = parseUrls(upstreamData);
+            } else {
+                let tabURL: string;
+                await queryUrl(tab)
+                    .then(u => {
+                        tabURL = u;
+                    })
+                    .catch(() => {
+                        e => {
+                            this._running = false;
+                            return Promise.reject(e);
+                        }
+                    });
+                urls = [tabURL];
+            }
+        }
+        return urls.reduce((p, url, i) => p.then(
+            results => {
+                if (i > 0 && results instanceof Array) {
+                    let lastURL = urls[i - 1];
+                    this.saveResult(results, lastURL);
+                }
+                if (this._data[url]) return;
+
+                let pms: Promise<any> = this.runningCheck(() => redirectTab(tab, url));
+                return pms
+                    .then(() => this.makeOptionalTasks(tab))
+                    .then(
+                        () => this.runningCheck(() => extractTabData(tab, this._itemsSelector, this._fieldSelectors))
+                    );
+            }
+        ), Promise.resolve<string[][]>(null)).then(
+            results => {
+                if (results && results.length) {
+                    let lastURL = urls[urls.length - 1];
+                    this.saveResult(results, lastURL);
+                }
+                this._running = false;
+            }
+        ).catch(
+            e => {
+                this._running = false;
+                throw e;
+            }
+        );
+    }
+    private makeOptionalTasks(tab: chrome.tabs.Tab): Promise<any> {
+        let pm: Promise<any>;
+        if (this._options["scrollToBottom"]) {
+            pm = this.runningCheck(() => scrollToBottom(tab));
+        }
+        return pm;
+    }
+    private runningCheck(fn: () => Promise<any>): Promise<any> {
+        if (!this._running) throw "The task is stopped by user.";
+        return fn();
+    }
+    private saveResult(results, key) {
+        if (this._data[key] === undefined) {
+            // do not add keys again
+            this._data_keys.push(key);
+        }
+        this._data[key] = results;
+        logger.info(`${results.length} items found.`)
+    }
+}
--- a/src/background/tools.ts
+++ b/src/background/tools.ts
@ -0,0 +1,62 @@
+import { ExtractResult } from "./result";
+
+const URL_REG = /^\s*(https?):\/\//im;
+
+export function parseUrls(...args): string[] {
+    if (!args.length) return [];
+    let arg = args.shift();
+    if (arg instanceof Array) {
+        return arg;
+    } else if (arg instanceof ExtractResult) {
+        return arg.squash().filter(v => URL_REG.test(v));
+    } else {
+        let urlTempl = arg;
+        if (urlTempl) {
+            if (args[0] instanceof Array) {
+                return args[0].map(p => urlTempl.replace("${page}", p));
+            } else if (args.length >= 3) {
+                let urls = [];
+                let from = args.shift();
+                let to = args.shift();
+                let interval = args.shift();
+                for (let i = from; i <= to; i += interval) {
+                    urls.push(urlTempl.replace("${page}", i));
+                }
+                return urls;
+            }
+        }
+    }
+    return [];
+}
+
+export function saveFile(data: string, mimeType: string, fileName?: string) {
+    fileName = fileName || document.title || "result";
+    let blob: Blob;
+    if (typeof window.Blob == "function") {
+        blob = new Blob([data], {
+            type: mimeType
+        })
+    } else {
+        var BlobBuiler = window.MSBlobBuilder;
+        var builer = new BlobBuiler();
+        builer.append(data);
+        blob = builer.getBlob(mimeType)
+    }
+    var URL = window.URL || window.webkitURL;
+    var url = URL.createObjectURL(blob);
+    var link = document.createElement("a");
+    if ('download' in link) {
+        link.style.visibility = "hidden";
+        link.href = url;
+        link.download = fileName;
+        document.body.appendChild(link);
+        var j = document.createEvent("MouseEvents");
+        j.initEvent("click", true, true);
+        link.dispatchEvent(j);
+        document.body.removeChild(link)
+    } else if (navigator.msSaveBlob) {
+        navigator.msSaveBlob(blob, fileName)
+    } else {
+        location.href = url
+    }
+}
--- a/src/common/index.ts
+++ b/src/common/index.ts
@ -0,0 +1,28 @@
+export enum Actions {
+    // from background to content script
+    EXTRACT = 1,
+    GOTO_URL,
+    PING,
+    QUERY_URL,
+    SCROLL_BOTTOM,
+    SLEEP,
+    WAKEUP,
+    // from popup to background script
+    UPLOAD_STATE,
+    // from content to background script
+    REPORT_NEW_PAGE,
+}
+
+export interface Request {
+    action: Actions
+    itemsSelector?: string
+    fieldSelectors?: string[]
+    url?: string
+    fileName?: string
+    state?: string
+}
+
+export interface Response<T> {
+    result: T;
+    error: string;
+}
--- a/src/common/logger.ts
+++ b/src/common/logger.ts
@ -0,0 +1,75 @@
+export enum LOGGER_LEVEL {
+    DEBUG = 1,
+    INFO,
+    WARN,
+    ERROR,
+    DISABLED,
+};
+
+export class Logger {
+    private _notificationId = undefined;
+    private _log_level = LOGGER_LEVEL.INFO;
+    private _notify_level = LOGGER_LEVEL.ERROR;
+    constructor(logLevel, notifyLevel) {
+        if (logLevel) this._log_level = logLevel;
+        if (notifyLevel) this._notify_level = notifyLevel;
+        if (chrome.notifications) chrome.notifications.onClosed.addListener((id, byUser) => { this._notify_level = undefined });
+    }
+    get logLevel() {
+        return this._log_level;
+    }
+    set logLevel(val: LOGGER_LEVEL) {
+        this._log_level = val;
+    }
+    get notifyLevel() {
+        return this._notify_level;
+    }
+    set notifyLevel(val: LOGGER_LEVEL) {
+        this._notify_level = val;
+    }
+    log(level: LOGGER_LEVEL, loggerFn: Function, ...msgs) {
+        if (level < this._log_level) return;
+        let time = new Date().toLocaleString();
+        loggerFn(`${time} [${LOGGER_LEVEL[level]}]`, ...msgs);
+        if (level < this._notify_level) return;
+        this.notify(...msgs);
+    }
+    debug(...msgs) {
+        this.log(LOGGER_LEVEL.DEBUG, console.debug, ...msgs);
+    }
+    info(...msgs) {
+        this.log(LOGGER_LEVEL.INFO, console.info, ...msgs);
+    }
+    warn(...msgs) {
+        this.log(LOGGER_LEVEL.WARN, console.info, ...msgs);
+    }
+    error(...msgs) {
+        this.log(LOGGER_LEVEL.ERROR, console.info, ...msgs);
+    }
+    notify(...msgs) {
+        let msg = msgs.join(' ');
+        if (!this._notificationId) {
+            chrome.notifications.create(
+                null,
+                {
+                    "type": "basic",
+                    "iconUrl": chrome.extension.getURL('icon.png'),
+                    "title": "Data Extractor",
+                    "message": msg,
+                    "priority": 0,
+                    "requireInteraction": true,
+                },
+                notificationId => {
+                    this._notificationId = notificationId;
+                }
+            );
+            return;
+        }
+        chrome.notifications.update(
+            this._notificationId,
+            { "message": msg }
+        );
+    }
+}
+
+export const logger = new Logger(LOGGER_LEVEL.DEBUG, LOGGER_LEVEL.DISABLED);
--- a/src/content/actions.ts
+++ b/src/content/actions.ts
@ -0,0 +1,101 @@
+import { logger } from "../common/logger";
+
+export function extract(itemsSelector: string, fieldSelectors: string[], expectedURL: string): string[][] {
+    if (expectedURL && location.href != expectedURL) {
+        throw 'Target tab URL changed, aborting...';
+    }
+    // since some elements may be loaded asynchronously.
+    // if one field is never found, we should return undefined,
+    // so that senders can detect to retry until elements loaded.
+    // If user writes wrong selectors, the task retries infinitely.
+    let fieldFound: { [key: string]: boolean } = {};
+    let items: Element[] = Array.from(document.querySelectorAll(itemsSelector));
+    // items may not loaded yet, tell the sender to retry.
+    if (!items.length) return [];
+    let results: string[][] = items.map(
+        item => {
+            return fieldSelectors.map(
+                selector => {
+                    let doClick = false;
+                    if (selector.startsWith("!")) {
+                        doClick = true;
+                        selector = selector.substring(1);
+                    }
+                    let [cls, attr] = selector.split('@').slice(0, 2);
+                    let fieldElements: Element[];
+                    cls = cls.trim()
+                    if (cls != "") {
+                        fieldElements = Array.from(item.querySelectorAll(cls));
+                    } else {
+                        fieldElements = [item];
+                    }
+                    if (!fieldElements.length) {
+                        return;
+                    }
+                    fieldFound[selector] = true;
+                    return fieldElements.map(find => {
+                        if (doClick) {
+                            let e = document.createEvent("MouseEvents");
+                            e.initEvent("click", true, true);
+                            find.dispatchEvent(e);
+                        }
+                        return attr ? find[attr] : find.textContent.trim();
+                    }).join('\n')
+                }
+            )
+        }
+    );
+    // TODO: configurable wait logic
+    // if it exists a field, which is not found in any row, the sender should retry.
+    let notFoundFields = fieldSelectors.filter(f => !fieldFound[f]);
+    let shouldWait = notFoundFields.length > 0;
+    if (shouldWait) {
+        logger.debug('should wait for:', fieldSelectors.filter(f => !fieldFound[f]).join(','));
+    }
+    return shouldWait ? [] : results;
+}
+
+export function scrollToBottom() {
+    return executeUntil(
+        () => window.scrollTo(0, document.body.clientHeight),
+        () => document.body.clientHeight - window.scrollY - window.innerHeight < 20,
+        "Scroll to page bottom...",
+        1000,
+        10
+    );
+}
+
+/**
+ * Repeatedly execute an function until the the detector returns true.
+ * @param {object} fn the function to execute
+ * @param {object} detector the detector.
+ * @param {string} log messages logged to console.
+ * @param {number} interval interval for detecting
+ * @param {number} limit max execute times of a function
+ * @return {Promise} a promise of the response.
+ */
+function executeUntil(fn: () => void, detector: () => boolean, log: string, interval: number, limit: number) {
+    interval = interval || 500;
+    let count = 0;
+    return new Promise<boolean>((resolve, reject) => {
+
+        loop();
+
+        async function loop() {
+            fn();
+            limit++;
+            if (limit && count >= limit) {
+                reject(false);
+            }
+            setTimeout(() => {
+                let flag = !detector || detector();
+                if (log) console.log(log, flag ? '(OK)' : '(failed)');
+                if (flag) {
+                    resolve(true);
+                } else {
+                    loop();
+                }
+            }, interval);
+        }
+    });
+}
--- a/src/content/index.ts
+++ b/src/content/index.ts
@ -0,0 +1,75 @@
+import { Request, Actions, Response } from '../common';
+import { scrollToBottom, extract } from './actions';
+
+let asleep = false;
+chrome.runtime.onMessage.addListener(
+    function (request, sender: chrome.runtime.MessageSender, sendResponse: (r: any) => void) {
+        if (!request.action) return;
+        if (asleep && Actions.WAKEUP != request.action) {
+            sendResponse && sendResponse(undefined);
+            return;
+        }
+        // console.log("Recieved request:",request);
+        doAction(request, sender).then(r => sendResponse && sendResponse(r));
+        // return true to indicate you wish to send a response asynchronously
+        return true;
+    }
+);
+
+chrome.runtime.sendMessage(<Request>{
+    action: Actions.REPORT_NEW_PAGE,
+});
+
+async function doAction(request: Request, sender: chrome.runtime.MessageSender): Promise<Response<any>> {
+    let result: any;
+    let error: string;
+    try {
+        switch (request.action) {
+            case Actions.EXTRACT:
+                result = extract(request.itemsSelector, request.fieldSelectors, request.url);
+                break;
+            case Actions.GOTO_URL:
+                window.location.replace(request.url);
+                // should not recieve any request until the page & script reload
+                asleep = true;
+                result = request.url;
+                break;
+            case Actions.PING:
+                result = "pong";
+                break;
+            case Actions.QUERY_URL:
+                result = window.location.href;
+                break;
+            case Actions.SCROLL_BOTTOM:
+                result = scrollToBottom();
+                break;
+            case Actions.SLEEP:
+                asleep = true;
+                result = "Content script is sleeping.";
+                break;
+            case Actions.WAKEUP:
+                asleep = false;
+                result = "Content script is available.";
+                break;
+            default:
+                error = 'Unsupported action.'
+                break;
+        }
+    } catch (err) {
+        if (err instanceof Error) {
+            error = err.message;
+        } else {
+            error = err;
+        }
+    }
+    return newResponse(result, error);
+}
+
+
+function newResponse<T>(result: T, err?: string): Response<T> {
+    let r: Response<T> = {
+        result: result,
+        error: err,
+    }
+    return r;
+}
--- a/src/popup/index.ts
+++ b/src/popup/index.ts
@ -0,0 +1,34 @@
+import { Request, Actions } from '../common';
+
+window.onload = function () {
+    document.querySelector('#link-extension-detail')
+        .addEventListener('click', () => {
+            chrome.tabs.create({
+                'url': `chrome://extensions/?id=${chrome.runtime.id}`
+            });
+        })
+    document.querySelector('#link-document')
+        .addEventListener('click', () => {
+            chrome.tabs.create({
+                'url': `https://git.qjebbs.com/jebbs/data-extracter-extesion`
+            });
+        })
+    document.querySelector('#state-input')
+        .addEventListener('change', function (...args) {
+            if (this.files.length == 1) {
+                var reader = new FileReader();
+                let fileName = this.files[0].name;
+                reader.readAsText(this.files[0], "UTF-8");
+                reader.onload = function (evt) {
+                    var fileString = evt.target.result;
+                    chrome.runtime.sendMessage(<Request>{
+                        action: Actions.UPLOAD_STATE,
+                        state: fileString,
+                        fileName: fileName
+                    }, r => {
+                        if (r) console.log('State sent:', r);
+                    });
+                }
+            }
+        });
+}
--- a/styles/bootstrap.min.js
+++ b/styles/bootstrap.min.js
--- a/template/assets/bootstrap.min.css
+++ b/template/assets/bootstrap.min.css
--- a/template/assets/console.png
+++ b/template/assets/console.png
--- a/template/html/popup.html
+++ b/template/html/popup.html
@ -3,11 +3,9 @@
 <link>
 <meta charset="utf-8">
 <title>Data Extractor</title>
-<script charset="UTF-8" type="text/javascript" src="../scripts/jquery.min.js"></script>
-<script charset="UTF-8" type="text/javascript" src="../styles/bootstrap.min.js"></script>
-<script charset="UTF-8" type="text/javascript" src="./tip.js"></script>
+<script charset="UTF-8" type="text/javascript" src="../scripts/popup.bundle.js"></script>

-<link rel="stylesheet" href="../styles/bootstrap.min.css">
+<link rel="stylesheet" href="../assets/bootstrap.min.css">
 </head>

 <body style="margin: 20px 10px;">
@ -20,20 +18,19 @@
        <div class="row">
            <div class="col">
                <div class="alert alert-info small">
-                    <!-- <h6>Usage:</h6> -->
                    <p>
                        Goto <a href="#" id="link-extension-detail">Extension Detail</a>, click "backgroud page",
                        and type your scripts in the console.
                    </p>
                    <p>
-                        <img src="../images/console.png" alt="" style="max-width: 489px; width: 100%; border-radius: 5px">
+                        <img src="../assets/console.png" alt=""
+                            style="max-width: 489px; width: 100%; border-radius: 5px">
                    </p>

                </div>
            </div>
        </div>
        <div class="row">
-
            <div class="col">
                <h6>Quick Start</h6>
            </div>
@ -43,22 +40,33 @@
                <div class="alert alert-success small">
                    <p>
                        <b>Extract current page</b>:
-                        <br>new Extractor().task(".list-item", ["a.title", "p.content"]).start();
+                        <br>&gt; $(".list-item", ["a.title", "p.content"]);
                    </p>
                    <p>
                        <b>Extract multiple pages (1-10, interval 1)</b>:
-                        <br>new Extractor().task(".list-item", ["a.title", "p.content"],
-                        "http://sample.com/?pn=${page}", 1, 10, 1).start();
+                        <br>&gt; job=new Extractor().task(".list-item", ["a.title", "p.content"],
+                        "http://sample.com/?pn=${page}", 1, 10, 1);
+                        <br>&gt; job.start();

                    </p>
                    <p>
-                        <b>Full document:</b>
+                        <b>Full document at:</b>
                        <br>
-                        <a href="#" id="link-document">https://git.jebbs.co/jebbs/data-extracter-extesion</a>
+                        <a href="#" id="link-document">https://git.qjebbs.com/jebbs/data-extracter-extesion</a>
                    </p>
                </div>
            </div>
        </div>
+        <div class="row">
+            <div class="col">
+                <h6>Saved State</h6>
+            </div>
+        </div>
+        <div class="row">
+            <div class="col">
+                <input type="file" name="state" id="state-input">
+            </div>
+        </div>
    </div>
 </body>

--- a/template/icon.png
+++ b/template/icon.png
--- a/template/manifest.json
+++ b/template/manifest.json
@ -1,7 +1,7 @@
 {
  "manifest_version": 2,
  "name": "Data Extracter",
-  "version": "0.1.0",
+  "version": "0.5.1",
  "author": "jebbs",
  "description": "Extract data from web page elements as sheet.",
  "icons": {
@ -11,29 +11,25 @@
  },
  "browser_action": {
    "default_icon": "icon.png",
-    "default_popup": "popup/tip.html",
+    "default_popup": "html/popup.html",
    "default_title": "Data Extracter"
  },
  "background": {
    "scripts": [
-      "scripts/background.js",
-      "scripts/result.js",
-      "scripts/tools.js",
-      "scripts/extract.js",
-      "scripts/extractor.js"
+      "scripts/background.bundle.js"
    ],
    "persistent": false
  },
  "content_scripts": [{
    "matches": ["*://*/*"],
    "js": [
-      "scripts/jquery.min.js",
-      "scripts/content.js"
+      "scripts/content.bundle.js"
    ],
    "run_at": "document_idle"
  }],
+  "incognito": "spanning",
  "permissions": [
    "activeTab",
-    "storage"
+    "notifications"
  ]
 }
--- a/tsconfig.json
+++ b/tsconfig.json
@ -0,0 +1,12 @@
+{
+    "compilerOptions": {
+        "module": "commonjs",
+        "target": "es6",
+        "noImplicitAny": false,
+        "sourceMap": true,
+        "rootDir": "src",
+        "outDir": "dist/js",
+        "noEmitOnError": true,
+        "typeRoots": [ "node_modules/@types" ]
+    }
+}
--- a/webpack.config.js
+++ b/webpack.config.js
@ -0,0 +1,33 @@
+const path = require('path');
+const CopyPlugin = require('copy-webpack-plugin');
+
+module.exports = {
+    mode: 'production',
+    entry: {
+        background: './src/background/index.ts',
+        content: './src/content/index.ts',
+        popup: './src/popup/index.ts',
+    },
+    // devtool: 'inline-source-map',
+    output: {
+        path: path.resolve(__dirname, 'dist'),
+        filename: 'scripts/[name].bundle.js'
+    },
+    module: {
+        rules: [
+            {
+                test: /\.tsx?$/,
+                use: 'ts-loader',
+                exclude: /node_modules/
+            }
+        ]
+    },
+    resolve: {
+        extensions: ['.tsx', '.ts', '.js']
+    },
+    plugins: [
+        new CopyPlugin([
+            { from: '**/*', to: '.', toType: "dir" },
+        ], { context: 'template', logLevel: 'warn' }),
+    ]
+};
Author	SHA1	Message	Date
jebbs	e87e7010ec	improvements * chance to continue on mismatch url for redirectTab * support empty field selectors * add Extractor.results() * add ExtractResult.walk(), ExtractResult.visit() * add ! directive to click elements * code optimize	2021-04-20 14:20:05 +08:00
jebbs	108ebb835f	fix task running state	2021-04-20 12:01:10 +08:00
jebbs	e0b0a5e986	add timeout for messaging	2021-04-20 12:00:59 +08:00
jebbs	9cd25e3c1d	update url	2021-04-19 15:58:04 +08:00
jebbs	7827d385bd	refactor	2020-06-16 14:45:36 +08:00
jebbs	ade0670415	update readme	2020-01-17 11:01:13 +08:00
jebbs	63aec616b1	code optimize	2020-01-17 09:38:40 +08:00
jebbs	378883b626	check url change before extract data	2020-01-16 15:11:49 +08:00
jebbs	c78f593c70	code optimize	2020-01-16 09:59:19 +08:00
jebbs	d82010686d	Extractor.watch() improvements - only watch current window - stop watch on window close - don't ask user to confirm when fails	2020-01-15 18:28:28 +08:00
jebbs	7644a1363f	Extractor.watch()	2020-01-15 17:53:23 +08:00
jebbs	3338f78d91	code optimize	2020-01-15 15:21:17 +08:00
jebbs	da7ae057f4	Extractor.stop()	2020-01-15 14:18:31 +08:00
jebbs	2224db1ad1	incognito window first	2020-01-15 14:05:57 +08:00
jebbs	790c95ffc3	clean state cache in 30 seconds	2020-01-14 17:03:14 +08:00
jebbs	f06a6f4e78	migrate to typescript, with fixes	2020-01-14 16:37:50 +08:00
jebbs	3d375261df	fix task._data_keys not cleaned	2020-01-13 16:55:40 +08:00
jebbs	13e233fbe7	allow user decision when some action fails	2020-01-13 16:47:52 +08:00
jebbs	21d3dfb247	small fixes	2020-01-13 16:45:54 +08:00
jebbs	97c8aac58d	add logger	2020-01-13 14:27:40 +08:00
jebbs	09112bb506	update documents	2020-01-12 16:54:24 +08:00
jebbs	c7f4fe7cc4	save and load state	2020-01-12 16:19:38 +08:00
jebbs	f1cf32b83a	availablity check before run on active tab	2020-01-11 20:40:25 +08:00
jebbs	341abebc66	scrollToBottom option	2020-01-11 20:00:52 +08:00
jebbs	0cf04c3f79	keep state and continue	2020-01-11 09:02:12 +08:00
jebbs	6134289d0a	queryUrl expected url	2020-01-10 16:35:57 +08:00
jebbs	0e62d914c1	runtime error do not interrupt promise chains	2020-01-10 16:34:46 +08:00
jebbs	c504942144	wait for elements	2020-01-10 15:35:18 +08:00
jebbs	4656e4ff64	helper function $	2020-01-10 13:22:37 +08:00
jebbs	26c6c1159e	refactoring	2020-01-10 12:07:21 +08:00
jebbs	51da68fee5	improved log	2018-09-29 15:25:03 +08:00
jebbs	69ea3cf69b	running detect	2018-09-29 14:44:15 +08:00
jebbs	7e782c633a	better task tab management	2018-09-29 14:37:24 +08:00
jebbs	ecd8a0d3d8	improve invalid arguments processing	2018-09-29 13:32:13 +08:00
jebbs	556316a021	fix a typo	2018-09-28 16:28:05 +08:00